It is common to place cameras on vehicles for purposes of providing one or more images of areas surrounding the vehicle to an operator. This helps to improve the awareness of the operator relative to conditions near the vehicle for avoiding collisions and to assist in maneuvering the vehicle for parking or movement near loading docks or the like. For these reasons and for purposes of attempting to provide a “surround view” of the area around the vehicle, cameras have been located at various positions on the vehicle such as for example at the front end, rear, left side, and right side. These cameras offer the operator various views relative to the vehicle including forward, rear, left and right views. In some applications, the set of views are combined by abutting or “stitching” into a single image for display on the dashboard of the vehicle or the like to provide live panoramic or bird's eye views of the vehicle in its current setting for the convenience of the operator.
Combination of the several views provided by the separate cameras is complicated. Calibration of the cameras and of the overall surround view system provides the best results, but this step further complicates the installation. Some surround view camera systems are simply installed and used without calibration, but vehicle operators find these resultant composite images to be difficult to interpret. Other surround view camera systems use manual calibration techniques and still others use calibration targets placed in specific zones where adjacent camera images overlap. However, these techniques are time consuming and prone to error. Discrepancies between the respective individual images often manifest and this condition adversely affects the resultant overall composite or “stitched” image, particularly in the stitching zone. Also, the target placement and other requirements used in these calibration techniques restrict the flexibility of the calibration setup and also restrict the situations where automatic run-time calibration can be used.
It is therefore desirable to provide a vehicle 360° surround view system without these limitations and which provides realistic life-like images to a vehicle operator without introducing any mis-registration artifacts or other confusion into the image and, in particular, to provide a vehicle 360° surround view system having corner placed cameras, and systems and methods for easily and efficiently calibrating the surround view system.